I attempted to remove my cranks today, in an attempt to cure a slight clicking under high load. The bike is an '03 Klein Q-Carbon Team that I got on Ebay with Ultegra bits. When I tried to remove the crank bolt, the retaining cap came out, but the crank didn't. (It's a self-extracting type crank.) The threads on the retaining cap looked definitely stripped, and there were aluminum shavings present. The threads on the crank itself look good (thankfully).
So, is there anywhere I can purchase just the retaining cap? No luck so far looking on teh internets